It is known to provide a ram air turbine on an aircraft for powering an auxiliary or emergency hydraulic power supply of the aircraft in case of engine failure, for example. Typically, the ram air turbine is stowed in an up, stowed position where the turbine is inoperative during normal operation of the aircraft. In case of engine failure in flight, the ram air turbine is pivoted to a lower, deployed position where the blades of the turbine are exposed to the passing air stream for rotating the turbine blades. The output of the turbine drives a pump for the auxiliary or emergency hydraulic power supply. In the past, this pump has been located on the bottom of the turbine for direct drive by the turbine. However, it has been found to be preferable under certain circumstances to locate the pump for the auxiliary hydraulic power supply above the turbine and to employ an intermediate gear drive between the turbine and the pump for driving the pump.
A characteristic of an auxiliary power ram air turbine with variable pitch blades, during start-up, is limited torque when transitioning from coarse pitch to fine pitch blade position. The gear meshes in a gear drive between the turbine and the pump of necessity must be lubricated. Temperatures at high altitudes can be as low as -20.degree. F. to -85.degree. F. In accordance with the present invention, it has been found that the lubricating oil at these low temperatures is so viscous that the drag on the gear drive from the lubricating oil can undesirably delay or prevent start-up of the turbine when it is moved to the deployed position.
U.S. Pat. No. 3,810,528 to Morley discloses a turbine with a lubricant tank located remote from the gearing which is to be lubricated. U.S. Pat. No. 4,858,426 to Holcomb discloses a secondary oil flow operable in a vertical position and gravity fed from a remote reservoir tank 60. U.S. Pat. No. 4,856,273 to Murray discloses a secondary oil system including a secondary annular oil tank and discharge orifice which is gravity fed when in the vertical position. U.S. Pat. No. 4,683,985 to Hultgren discloses a remote sump in a lubricant system for a vertical shaft.